Earth’s Rapid warming in Late 20th Century Far More Widespread than Any Temperature Variations

In this image made from video, climate change protesters block the car containing Britain's Conservative Party leader Boris Johnson on his way to meet the Queen in London, July 24, 2019. VOA

Earth’s rapid warming in the late 20th century was far more widespread than any temperature variations during the previous 2,000 years, according to a study published on Wednesday that shows how profoundly humans have altered the climate.

The study crunched data covering two millennia from almost 700 sources ranging from tree rings and coral to sediments and ice cores.

Published in the journal Nature, it found that previous major climate events were confined to certain areas, and not global phenomena as scientists had previously assumed, said one of its co-authors, Columbia University climate scientist Nathan Steiger.

“The main takeaway is that climate variability in the contemporary period is very different than what’s happened in the past 2,000 years,” he said.

Earth’s rapid warming in the late 20th century was far more widespread than any temperature variations during the previous 2,000 years. Pixabay

Natural phenomenon?

Some people who question whether burning coal, oil and gas is causing global warming point to evidence of prolonged shifts in climatic conditions in past centuries to argue that today’s higher temperatures may also be a natural phenomenon.

Previous shifts include the “Medieval Climate Anomaly” from 800-1200 AD when temperatures rose, and the “Little Ice Age” from around the 1300s to the 1850s when Britons skated on the frozen River Thames.

But the study, which measured readings from zero to 2,000 AD, showed that some of the coldest temperatures during that period were more localized, occurring in parts of the Pacific in the 15th century and in northwestern Europe and southeastern North America in the 17th.

By contrast, the researchers found that the rapid rise in average temperatures in the closing decades of the last century affected more than 98% of the planet.

“This is definitely further evidence that fossil fuels and anthropogenic activity actually has fundamentally changed the climate,” Steiger told Reuters.

Volcanic activity

Mark Maslin, professor of climatology, at University College London (UCL) said the paper should “finally stop climate change deniers claiming that the recent observed coherent global warming is part of a natural … cycle.”

The study crunched data covering two millennia from almost 700 sources ranging from tree rings and coral to sediments and ice cores. Pixabay

A parallel study published in Nature Geoscience found that pre-industrial fluctuations in temperature were primarily driven by volcanic activity.

Tourists gather around the Capitol pond with the Washington Monument in the background on a hot day in Washington, DC as temperature rises into the upper 80s Fahrenheit, Friday, July 19, 2019. (Photo by Diaa Bekheet). VOA

The National Weather Service warned that dangerously high temperatures and humidity in the United States over the weekend could quickly cause heat stress or heat stroke, if precautions are not taken. The NWS advises people to check in on relatives and friends, especially the elderly.

Temperatures have been rising in cities from the Midwest to the East Coast because of a high pressure system that has trapped the warm air. City officials are allowing public pools to stay open longer and municipalities are issuing advisories to inform the public about how best to deal with the heat.

Forecasters say temperatures in New York City will reach 33 degrees Celsius Saturday, but with the humidity, it will feel like 43 degrees Celsius.

Saturday in the nation’s capital will reach 38 degrees Celsius and Philadelphia will go up to 36 degrees Celsius.

The National Weather Service warned that dangerously high temperatures and humidity in the United States over the weekend could quickly cause heat stress or heat stroke. Pixabay

The World Meteorological Organization says June 2019 was the planet’s warmest month ever. In addition, both land and sea temperatures set record highs in June.

June was also Europe’s hottest June on record, according to the WMO. Greenland, Alaska and parts of South America, Africa and Asia had temperatures substantially above normal in June, according to the WMO. The organization said India and Pakistan experienced a severe heatwave in the early part of June, before the onset of the monsoon season. (VOA)